At Los Angeles International Airport, two dry ice bombs exploded this week, and two others were found in a restricted area of the airport. According to the Los Angeles Times, the devices "appeared to be outside the terminal near planes where employees such as baggage handlers and others work on the aircraft and its cargo."

That reminds me: It's been more than a year since watchdogs warned Capitol Hill that our massive homeland security bureaucracy was neglecting these very areas of our nation's airports. Grandmas, babies and war heroes are routinely groped, manhandled and humiliated in the name of transportation safety. But untold numbers of ground personnel still have easy, breezy access to airplanes and luggage.

In August, seven baggage handlers at Kennedy Airport were arrested after being videotaped stealing jewelry, cash, watches and computers from passenger luggage. In June, a baggage handler at Atlanta's Hartsfield-Jackson International Airport was arrested after using his credentials to bypass airport security and carry backpacks containing what he believed were drugs and guns onto commercial flights. It's almost as if any bumbling bimbo can connive his or her way into supposedly secure territory.

A Nigerian illegal alien named Bimbo Oyewole did just that. He used a dead man's birth certificate and Social Security number to get a job with a private security firm at Newark Airport. Con artist Bimbo went undetected for more than two decades while supervising security guards who policed tarmacs, planes and cargo. Last summer, in the wake of Bimbo's belated bust, the DHS inspector general called for stricter background checks on baggage handlers, maintenance workers and other civilian airport employees.

But by the feds' own admission, legions of workers who were grandfathered into the system may yet be traipsing around restricted areas of our nation's airports — doing God knows what. TSA does not keep systematic records on airport security breaches reported to headquarters. "I'm going to tell you right now that the next incident is going to come from the ground," Rep. Chip Cravaack, R-Minn., testified last spring. "It's going to come from the shadow of the aircraft, not from the terminal. I'm telling you that."

Rest assured, however, that we are as vulnerable as ever to the old tried-and-true scheme of sending hijackers aboard planes to take them down. The U.S. Airline Pilots Association spelled it all out in a memo obtained by WTSP Tampa Bay reporter Mike Deeson last week.

"Bringing down an airliner continues to be the Gold Standard of terrorism," the document warned U.S. Airways pilots. "If anyone thinks that our enemies have 'been there, done that' and are not targeting commercial aviation — think again. There have been several cases recently throughout the industry of what appear to be probes, or dry runs, to test our procedures and reaction to an inflight threat."

The assessment bluntly described "a group of Middle-Eastern males" who boarded a flight at Reagan National Airport in Washington, D.C., for Orlando, Fla., on September 2. Onboard, the men made "a scene": running toward the flight deck door, loudly opening and shutting overhead bins, and making what appeared to be a coordinated attempt to distract flight attendants. Federal air marshals were concerned enough about the behavior to "make their presence known." The memo notes that a security search found "evidence of tampering" on the plane.

It's just the latest suspected dry run since the 9/11 attacks:

—In May 2011, Yemeni national Rageh Ahmed Mohammed al-Murisi rushed the cockpit door aboard American Airlines Flight 1561 shrieking, "Allahu akbar!" at the top of his lungs more than 30 times intending to take down the plane and kill everyone on board.

—In July 2011, Saudi Arabian national Saleh Ali S. Alramakh caused United Airlines Flight 944 from Chicago to Germany to divert to Cleveland after violating airline security rules during a bizarre meltdown. He locked himself in the bathroom when passengers were supposed to be seated, scuffled with flight attendants and had to be restrained by the flight crew and other passengers.

—In 2010, Pakistani national Muhammad Abu Tahir was sentenced to prison after disrupting AirTran Airways' Atlanta to San Francisco Flight 39. After defying flight attendants and locking himself in the bathroom, the plane was diverted to Denver. His immigration status and occupation were unknown, though he had lived in the U.S. since at least 2002.

—In 2004, 13 Middle Eastern men aroused the suspicion of federal air marshals, flight crew and passengers on Northwest Airlines Flight 327 with disruptive red-flag behavior at takeoff and landing.

—And in August 2001, one month before 9/11, actor James Woods witnessed four suspicious Middle Eastern males aboard an American Airlines flight from Boston to Los Angeles. Woods shared his fears with the pilot and filed a report with the FAA. His warning was ignored. Years later, the feds confirmed it was indeed a dry run and that 9/11 lead hijacker Mohammed Atta was on Woods' flight.

Feckless feds keep admonishing the rest of us to "say something" if we "see something." But what good will it do if they're asleep at the wheel, blind to corruption and deaf to jihad?